Isotopic study of the upper watershed of the Rio Abancan (Province of Catamarca, Argentina)

The upper watershed of the Rio Abaucan drains the main part of the water resources of a semi arid area in the northern Argentine Andes. An isotopic study of the flow pattern has been undertaken within the lack of relevant hydrological and hydrogeological data. Oxygen 18, deuterium and tritium data suggest that snow is not contributing to the recharge of the aquifers. The storage of the alluvial deposits capacity appears to be low. The working hypotheses drawn out from this study indicate that such a kind of study could be done in a systematic way in order to prospect the resources of the andine watersheds. In a more general way, the interest of the isotopic methodology in areas where few data are available and where the environmental isotope labelling is large, these are often the same, must be underlined